Ok so I know this has been discussed alot on here already so please bare with me. I'm considering rebuilding my motor hopefully but its a 53 block and I was wondering if I would be ok with keeping the 53 block or try to find another one. Its got 204,xxx miles on it an it hasnt cracked yet that I know of an my coolant stays at 190 and below. I know that 204,xxx miles is nothing for a Cummins but I figured since Im going to do an upgraded cam and have the head overhauled might as well do the whole thing . Now on to the main subject I want to put in a hamilton cam(188-208-106.5 LSA Cast Cam .310"/.320") an was wondering if I would have any problems when setting the cam at a 99 centerline. I also plan to have the head overhauled nothing fancy just a resurface, new seals, new valves, an new springs. Then have the blocked bored .020" over an have the crank checked out to see if it needs turning. Ive also thought bout sending my pistons, rod bearings, an main bearings sent to PolyDyn in Houston Texas to have their performance coating applied. They told me that the coating on the piston skirt will add .0005" - .0007" per side and add .0003"-.0005" on the bearings. So would I have to concerned with the added thickness on the pistons and bearings when I have the block bored and the main an rod bearings done? I would like to acheive around 350-450 to the rear wheels with this motor so if anyone has suggestions on what else to add while Im building it let me know Also could I use the tappet cover from a 12v with the breather tube for the crankcase breather instead of using the one on the front cover? All in all what would kind of price am I looking at to have this motor rebuilt?

Thanks for help or advice guys and so for rambling on and making the question soooo long