I've done a lot of investigation on using P heads, while I use long tube headers I had a set of short headers for P heads and same brand for non-P heads, prolly BBK back then, been a minute, and honestly I could not tell them apart, I even installed one set on my stock convertible but don't know which set

the factory headers looked like sht,
Like I said I use LTs on the Junk Pile and they are NOT P specific headers, can't get LTs specific for Ps any more, I will use a mix of different boots and also 'socks', the plug boot insulators like 'race cars' use, the only unresolved issue will be the dip stick tube/header tube/spark plug that occupy the same area, not much room between those two header tubes but you may not have this issue with short tubes, there is more room than Limps' pic shows, flange thickness will play a part in this, remember, thin, cheap material and you get rust and broken tube to flange welds, FRPP I believe should have a quality product but shop around, spark plug boot angle is, I believe, the only work a round.
Spring for Ceramic coating, NOT CHROME!
now the important stuff, how far should you go with install before start up,
everyone is a little different (duh!) I hook up everything! Just like I was gonna drive it down the road, especially if it's a new engine, just add water, like I was gonna run up the road, I actually did that last swap, a hour after start up I was do'n burnouts.
in your case you want to pre oil with pressure gauge to verify oil pressure, some turn the engine by hand one revolution while priming, fill with water, start up, bring it up to temp and run long enough to check leaks, possible future issues, get the headers hot so when you shut it down you can re-torque the bolts, check valve cover bolts, throttle body nuts, intake tubes tight, stuff like that.
It's gonna smoke a little in the dog house from residual oil, greasy fingerprints and prolly stink a little, after all you did paint it red (??), Ford gray or black works better JMO so have a good fan in the garage or be outsde, after shut down check for leaks, check you nuts and bolts, clamps, run codes, deal with any catastrophes like all that oil you just dumped in the drive because the oil filter was just a little loose.
