sorry i have been at SEMA for the past week. the 4.3, 700r,np205 worked just fine the rear drive shaft on mine with toyota mini truck axles and 4" mini truck lift springs is 22". i pushed my motor as far forward as i could this put a gap of about 8 inches from the the back of the heads to the fire wall. everything so far on it has been great but i did have to notch the frame a 1/2 in on the passenger side to alow the side of 205 to fit but i welded another plate on the outside of the frame as well as the re boxing the inside of the frame. I just cant wait to get this thing done and get to start driving it. The ground up on my rover has been about 5 years and 45 grand so far and still not done. But she will be nice when she is done.
Looking forward to seeing some pics when you have them. Don't feel bad about that 45k- I spent a lot more than that to have Lanny Clark restore my Series II. Mine is much nicer than anything that ever came off Solihull's line but it's completely stock with 1940's technology (underpowered by today's standards, drum brakes, etc). In the end you'll have a cool, unique ride with a "modern" drivetrain that you'll be excited to drive. If I had it to do again, your approach is the one I'd take. Keep us posted!