I'm going to be replacing my lower intake gasket on my 1999 gtp with 213,000 miles.I'm replacing everything wearable that is removed and valve cover gaskets and exhaust manifold gaskets,and polishing intake ports on lim.and porting the exhaust manifolds.Is there any lowbuck things for performance or otherwise that anyone can point me to,or any don't or becarefull not to f**k that up anyone can think of. Thank you