I finally decided that I'm going to rebuild the engine in my '78 D150. It needs the manifold gasket redone again, and since I have to rebuild the 4-speed anyway I figure I might as well get it all done.

My first question is, where should I buy a rebuild kit? Lots of different places sell them and I honestly don't have a clue what the difference is. Also, do I really need new pistons? Most of the "deluxe" kits come with a cam and oil pump (which I want), but also a new set of pistons, which seems to add quite a bit to the price.

Second question is machine work. I'm assuming the crank is fine, but I'd like the head redone. What should I have done, and about how much will it cost me? I can't get any place to give me a good quote without telling them EXACTLY what I want done.

Third question is maybe adding a few HP. I'm guessing the stock compression ratio is 8.5 or 8.7 to 1, can I get any more than that without having to use premium gas? Any kind of mild cam recommendations other than stock? Or would the fuel economy tradeoff not be worth it?

Thanks in advance for any tips!

My 2 cents, do the 4-speed first and do the engine as a seperate project.
For the engine, see if you can find a cheap (or free) core to rebuild on the side, then swap it in when it's ready.

As for all the datails, no one knows what is inside your (or any) engine until you take it apart and measure a few things.
How many miles are on it? If it's under 100k you may be able to put in new rings and bearings, redo the head, and be OK. (cylinders with more then .007 of taper should be rebored)

Compression ratio is the same deal, measure where it is now, adjust it based on real information and not on opinion. Cranking cylinder pressure (in psi) is a better thing to look at rather then static compression ratio numbers. What are your current engine cranking compression readings? Later Slants are lucky to be in the 130 to 140 psi range. (8 to 1 CR) Cam profile and cam advance has a lot of impact on cranking compression numbers.

A kit from PAW or your local parts store will be fine, the truth is that there is no longer a wide selection of different brands of rings, bearings etc. for the SL6
DD

Where can you get the 4 speed done at? assuming you are talking about an A-833. Most of the information I have seen states there isn't a lot of parts available anymore. I'm not sure, it's a pretty common tranny. Is this something the average transmission shop should be able to handle?

There's a company called Passon Performance online that does nothing but 833's... I got a recommendation for a place here in St. Cloud, but they quoted me $1,000-$1,500, which was a BIT out of my price range. I just ordered a rebuild kit from a company here in MN, but I forget the name... if you search ebay for A-833 you'll find some of their stuff, their website has a big selection.

A local shop quoted me between $400 - $900 for a rebuild on an A833. The $900 was if I needed to replace the gear sets. The $400 was only for bearings and syncros.

Before I rebuilt my last engine I checked the compression ratio and it wasn't very much. I than milled the head .060" and the block .030".
I used fluid to CC the head,head gasket and cylinder block and came
up with 8.9-1 compression. With a stock camshaft I still can use the cheap
grade of gas. This also gave me more power.