90 burb 4x4 350 has 700r4 swapping to th400

[chevy4ever]

Hey guys. I have a 90 burb 1/2 4x4 with 350 and 700r4. Lost 3rd and 4th gear coming back from the beach. I found me a th400 with the 204 transfer and torque converter. The guy only wants 350 its a friend of a friend. The tranny came out of a k10 blazer mid 80s but it wasnt the orig tranny. That blazers 350 wasnt running so the guy put in a 305 to test tranny and it ran fine he said. He said he drove around for about 2 weeks around town before he pulled it out and its been sitting in a project truck for 4 months. Fluid looks clean. Sounds like a good deal to me. From what im understanding the th400 is about an inch longer on the shaft than the 700r4. Im thinking i may have to scoot the cross member back possibly and then shorten the rear shaft and have to get another front shaft. The guy said he had a front shaft that will work if i need it. So what do you guys think? without knowin miles... i think its a deal and im gonna be jumping on it. Also my 700r4 has cable kick down. Im told this 400 has electronic kick down. How could i hook this up to work on my truck?

Also im puttin in a B&M zgate i got for free. Im taking out the middle console and building a new console with speaker mounts and something more sporty looking. Ill upload pictures as i work on it on my days off.