Here we go, I have a 93 lighting that had 465hp 502's stock, I just built 557 ci from 540 dart blocks,I have stelling extension boxes with the stelling inner transom plates. I am tiring to put the motors back in and the stelling inner plates where the bellhousings mount to them are about 3/16 of an inch closer to the transom then the stock plates were and not allowing me to mount the motors. I laid the stock plates on the fool next to the stelling ones and they come up 3/16 short just like they did in the boat. I called stelling and no answer. My fix is too mill a 3/16 plate to mount between the stelling plate and the transom??? What do ya think??

Motors are not tall decks either

As long as the drive shaft is not ending up to short,,,,ofcoarse !!!!
Should not be a problem !!!!!

Drive shaft is a slipyoke so should be no issue there.

Why dont you make a spacer to go between your engine plate and the stringer bracket? I assume this is where the issue is...

+ 1

I'd wait for word back from Stellings before modifying too much, may have had a bad batch ya never know. Otherwise I'd have to agree with the above (spacer between engine plate and stringer bracket). Or since it sounds like you have access to a mill, re-fab the stringer bracket with thicker material and take it down to the new thickness you need.

I think he is talking about the reg. bravo bellhousing mount ( NOT A RACE MOUNT ) so the 2 ears on the bell will sit on the inner transom plate !!!!!

On all the boxes i have used in the passed ,,,i just cut an aluminum plate as the inner and use rear "race" motor mounts.
Then there is no issui at all.

But i think i know what he is talking about and yes it will work if the slip yoke is long enuff.

I read wrong. I thought he was saying that the engine was to far in front of the brackets. It sounds like it is trying to set down on top of them.