I've been considering this same swap.
But I have a question.
Would it be as easy to remove the pickup truck sheet metal off it's chassis and put the Blazer on it?
It would give you a 'true' 5/4 ton Blazer. I'm not talking about trying to hack an M1008 up to make it if. I'm curious if it would drop on?
Also not trying to hijack this thread. But it IS germain to the thread. OP is going half way on this conversion in that he only replaced axles, though he may also be replacing the springs as well.
If all you did was yank the old body off an M1008 and then swapped in an M1009 onto it's chassis, would it fit? Too long a chassis? Just not sure.
I saw M1008's going for around $500 - $1000 at the last GSA auction I attended. While this would give me all the parts (and then some) to do this type of swap and the price is right, could I just yank the body off?
Sorry for the stupid question.
Edit: IF NOT A BLAZER, how about a Suburban as a donor vehicle?