If you need to verify the timing, you can do that yourself on the build stand. Just put your finger over the number one spark plug hole, turn the crankshaft clockwise, and whenever your finger starts to blow away from the hole, just line up the balancer mark with the zero, and voila! You have TDC on the #1 compression stroke. That’s the verification part, which I would assume all that is okay anyways. Setting the timing follows. Just set it to 10* initial BTDC and see how it does. If it can take more, give it more. If it pings, dial it back. You can alternatively opt for the total timing route, which would make an initial setting just a starting point rather than the definite, and even do a distributor recurve if you feel the need, but all of this is very simple. The moral of the story is you can save money by doing this yourself, and if you have a build stand/run stand, it’s pretty cozy. Add in a tachometer and a cheap timing light or just a fancy timing light, and you’re golden.
@74 Shortbed is the guy to talk to on that stuff. As far as the intake goes, I think it’s worth it, and you can find a used Edelbrock 2101 for $50-$75 dollars. Absolutely no more than $100. It is a design improvement over a factory cast iron intake. Plus it looks good, it makes assembly a bit easier, and you should gain 15hp give or take. Finally, I would recommend checking for timing chain play while you’re tinkering with timing and what not. If it’s a higher mileage motor, I’d consider replacing the timing set, and if you decide to get a new cam and lifters, I’d definitely do it. The harmonic balancer will also degrade over time, and it’s a piece of cake to replace without accessories or and engine bay to contend with. With that, look for a warped, cracked, or dry rotting rubber dampener between the two rings.