I'm going to chime in here.
I have a different interpretation of which bolts you're talking about.
I believe the bolts you are referring to are the bolts that hold the first section of the tail pipe to the tail pipe end of the manifold.
All these are a little different. On my '87, with the "factory headers" (welded manifold with an expansion joint between the front pair and rear pair of cylinders) the bolts (actually studs) on the drivers side are longer than the curb side due to the fact that the vacuum controled exhaust valve is sandwiched between the manifold and the tailpipe (this device encourages quick engine heating).
Since you probably have fuel injection on your '88, you may not have this valve.
I started to drop the valve out so I could inspect the internals, but the first stud I attacked took an internal twist, did not break loose, but did not torque off. Rather than have to drill the stud out (or worse), I just left it alone.
The good news is that there is enough room to work in the area without having to take off too many accessories.
The curb side is a little tighter, due to the proximity of the starter.
Bottom line is, from my observation, hoping to remove only the studs is wishful thinking. Plan on the studs torqueing off befor they back out.
If you do try to back them out, conjur up a lot of patience.
Heat, heat, heat, tap, tap, tap, soak, soak, soak.
Like the signature lines of one of the forum members, a quote from Mr. Turbo and Bog Frog.
"If you get it REAL hot, and hit it REAL hard, somethin' has GOT to give.
"Suck it up, spend the bucks, do it right the first time."
WBCCI # 1113
Trailer '78 31' Sovereign
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