From my experiances i have not had to use the "bright mark". In theory you shouldn't either, you just have to line up the mark on the cam to 12 0'clock and make sure you are on top dead center in the #1 cylinder. I also know from experiance that it is quite easy to miss a tooth on the cam sproket but that is a very noticable mistake.
I can say that to cheak the timing, first use the ditributor and a timing light (dont forget to disable the advance) and if you cant seem to get the mark in the right spot with only minor tweeking of the distributor than you need to investigate a little bit deeper.
Another note is if you have an aftermarket cam they some times need to be "degree'd". Now most quality cams already grind that in to the profile of the cam from their factory. There should be a booklet with the cam that explains how to do it if that is the case.
About the injectors with that much milage, well i just hope they have been cleaned sonner than 225k. How ever if they have not there are some over the counter cleaners( I.E. lucas fuel treatment) that have the right idea and work a little but if you really want your fuel rail and injectors clean try finding a shop with a Motor Vac, thats the name of the machine. and see if it fits your budget to have them do that to your motor. it will clean the carbon out of your motor to almost spotless, and i mean that. i have personally taken a motor apart that has had that done to it with ~200k with no other cleaning prior. The motor parts were damn near shinny. BTW the reason for the cleaning was poor runability and it helped but after the tear down the reason for the motor failure was the idgiot had RTV'd the hell outta the gaskets and the water passage's to the #3 cylinder were 3/4 blocked by Squished out RTV(the others were only half blocked <img src="/forums/images/graemlins/notooth.gif" alt="" />) so the cylinder over heated and blew the head gasket there.
One last note is that is also normal to see the power band of these 22r series motors litteraly kick in at 3-3500 RPM, thats normal operation, and they arnt know for there power either. Especially when you are pulling 33's with stock gearing.
