Yes, you can put the bottom mount arms in the top. But you will need to make a new front end. The bottom tube will need to be longer. To work out how much longer you will need to position the arms in a standard type frontend and measure the offset between the upper and lower arms, to do this, just place a straight edge on the lower arm at the face where the link pin goes in, and measrue the gap at the top arm in the same place.
From memory it is about 10mm. To achieve the same offset when the arms are swapped from the top to the bottom tube, you will need to be double it. eg 10mmx2 is 20mm AT BOTH ENDS.
I have done this many times with no problems. If you are going to make the shock mounts progressive(tipping forward) you will also need to modify the mounts on the arms as well.
Hope this helps Boss Truck!

While l am asking for advice we are building a new class 1 A/arm car as well and are at shock selection stage for the front we are looking at 2x2" 12" travel coilovers and 2x2" 14" travel dual bypass all Fox pro series any thoughts and susgestions would be much apprieciated as this is our first A/arm car.

Boss,

RE the class 3 car and advantages to going off the top mount - leaning the shocks forward to getting the shock rate to work progressively is like a cheap way of variating the shock characteristics at different points of travel.  IE, the shock piston moves less inside the shock for greater wheel travel at full droop, therefore has less resistance.  At full jounce the shock piston is moving at the same speed as the wheel traveling up and is therefore working harder, therefore has more resistance.  So if your going over little bumps while the wheel is drooping the wheel might travel 4 inches, but the piston will only move 2.  If your coming off a jump etc and bottoming out the front end the wheel will travel 4 inches and the piston will move the same.  As it has to push more fluid through the piston it has more resistance.

Wow - just reread that and made a simple action sound complicated.  Sorry!

Bill Croft gave us the best setup advice when we did our class 2 Rivvy - Go full bump (for us it was dropping the chassis to 75mm clearance) and mount the shocks 90deg to the arm. 

One good shock/coil per corner on the front of a class 3 should work if the car is light enough.  There's a bloody fast one in NSW (Gough) with singles on each corner to keep the weight down and it flies.  Shane Sansom ran 2 though when he won class 3 nationally and NSW in the same year.   Dont know enough about bilsteins to know if they are up to the job on thier own.

RE the A Arm car - we went with fox 2.5.  It was a balance for us between budget and performance... basically there are alot of class 10s in thestates running what we've put in, so we used their example as our starting point.  14" coils and 18" bypass on the rear (23" travel) 14" coil and no bypass on the front (21" travel)  We kept room on both the chassis and arm to mount a bypass on the front later if we want when the money is available. Dont know how well its going to work yet...  :) but its the best we could get for what we were willing to spend.

Wolf thanks for the info it will go a long way with our decisions. We are putting the old rivmasta on a diet to run class 3 and the new one will run pro class with a 4 litre toyota so we hope to see you at Donald and the east coast nationals next year. I had a look through my Dirt Comp mags and read Aus 1 is running 2" coilovers with 2.5" bypass and we can see his results. Our choice is money driven as well so l think the 2" 2 tube bypass will have to suffice for now on the front. l am though looking for some cheap second hand 12" travel coilovers the the back of the class 3 so if anyone has any it doesn't matter if they need a rebuild please P.M. me.

Ringo thanks for the info as well it all helps.