Upper and lower removed. Oil slude in upper plenum. Stovepipe sheared and plugged with hard oil slude. Upper part of LIM pooled oil in corners left rear/right front-lowest part of lim.No evidence of coolant in lifter valley. Please post a pic of lim stovepipe bore, so I can compare it to my bore.

I doubt your stovepipe sheared. For a stock '95, the OD of the stainless steel stovepipe is .749-.750" The walls are about .035" Can you measure the bore in the LIM? If it is .750", your stovepipe did not shear. From your pix, it appears that your stovepipe was loose, lifted up from engine vacuum and stuck in the UIM bore.

You need a new reduced diameter stovepipe. Buy an APN kit and you will be good to go. When you install the pipe, make sure it is tight in the bore. Looking for some pix for you..... Here is a .750" bore from a '95.

Have you read Techinfo Article 38? [

Bill you are indeed correct Measured inner bore after good cleaning
and it is .745 . Looked at new stovepipe from APN upper kit and did dryfit.
Fits perfect. Forgot stock GM stovepipes are one complete OD.
Thanks for your invaluable input and pic. .