? re shredded impeller & draining

Hey guys & gals ... 2004 Sanger V215 w MerCruiser ...

Had a fairly serious impeller failure on the first time off the trailer this summer (I'll try to post pictures later). Thanks to the threads on WakeWorld, SangerNation, and YouTube, I believe I have successfully changed the impeller. However before I put everything back together, I have a few questions for the more informed among us;

I have been advised to "remove & clean all the little bits and pieces of the failed impeller" from the transmission cooler, hoses, exhaust risers, and any screens" ... I have pulled all the little blue drain plugs. When it comes to draining the exhaust risers and cleaning those out, can anyone give me some instruction and/or pictures as to the best way to perform this? Do I need to remove the large allen-keyed metal plugs from the bottom of the exhaust risers?

Also, I am having a next to impossible time removing the hose that goes from the water pump up to the transmission cooler, from off the transmission cooler fitting itself. Does anyone have any tricks/tips for this? I've tried prying around it and spraying a bit of LPS#2 to break the bonds, as well as twisting/pulling, and have not been able to get it to budge!

Lastly, if I am successful getting the hose off the transmission cooler, does anyone know if this Motor and Trans Cooler has a screen/filter in there to trap any foreign matter before passing into the cooler and onto the rest of the system?

Thanks everyone!