You need a bellhousing for a T98 to mate to a 401...the T18 to 401 wont work as the bolt pattern is different on the front of the trans...though maybe it could be drilled to work.
Then the stickout would have to work...there are stickout lengths from 6.5 or 7 inches out to 16 inches...this is thelngth from the front ofthe tran to the end of the input shaft. The stock unit is around 9 inchs...though I will look for the exact spec.
I dont know that there is a bellhousing that fits your need...
If the input stickout is wrong, the input from other t98's and maybe even t18's will intrchange...though there are at least 2 different spline counts and right and left hand rotation units in addition to the different stickout lengths...makes shopping in the junkyard a headache...
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