Since i picked up the M1133 Stryker I want to do a M997 ambulance to go with it i want to use Academys M997 as a donor kit and move all the ambulance related parts over to either Tamiya's M1025 ,Bronco's
M1114 or Academys newer M1151
and im wondering whch would the be the kit to use for a current M997

I would stick with the Academy base HMMWV kit. There are a couple issues to moving it to another chassis. First, I think you could only use Tamiya's M1025 since I don't believe any uparmored (M1114/M1151) ambulances were made. Also, The Academy and Tamiya kits are not the same size and the ambulance body will not fit onto the Tamiya HMMWV. The Academy kits are actually pretty good. They are still superior to Tamiya's in some ways, like underside details. Maybe add some PE and/or resin upgrades and you should be good.

Gino is right about issues to moving Academy's ambulance shelter to another chassis. But there are ambulances on newer versions of Humvee - M997A3.

Kuba is correct. My Infantry Battalion has M997A3 ambulances which is the original ambulance box fitted to the M1152 HMMWV.

I think the M997A3 is only being fielded to US Army National Guard units. The active Army is waiting for the HMMWV replacement vehicle to make a new ambulance.

If it is built on the M1151, the ambulance body will probably fit onto the Academy M1151 then.

You are correct so far Gino. All of the purchase contracts to date have been for National Guard units.

I suggest not to go there. I thought of such a thing myself but the width of the kits ain't the same.
You'd be better off by sticking to the Academy kit and upgrade it with some after market wheels. Eduard has a PE set out if it's still available. If you have spare parts of newer HMMWV kits you can use them for better details such as front doors, lamps, radio, antenna base, seats and dashboard. Good luck.