The 250 is longer than the 216, and maybe slightly longer than the GMC inlines. You'll probably need to massage the radiator mounting position a little. Another sticking point will be the crossmember where the 216 bellhousing mounted- - - -the TH350 bell housing is a bit larger and shaped differently, so it will be difficult or impossible to get the engine/trans to fit at the right angle without doing a little whittling back there. DO NOT REMOVE THE CROSSMEMBER ALTOGETHER! It's also there to brace the rear of the front springs and add stiffness to the frame. Even if you do choose to use an IFS (Big mistake in my opinion) be sure to fabricate a dropped crossmember to reinforce the frame when you remove the original crossmember.

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Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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