Not sure if this belongs in a different thread or not???

I have a pretty serious oil consumption problem on my 07 650 Max after partial rebuild. 2700 miles, problem started with timing chains and guide problems, engine starved on oil and toasted rod bearings. Crank mic’d out ok for standard rods and mains…purchased new rods from mrrpm, installed new main bearings, installed updated timing chains and all the guides, reassembled with new case gaskets, new head gaskets, new valve cover gaskets, etc. Machine runs great, plenty of power, etc. but it consumed a quart of oil in the course of 80 miles of trail riding. …did a little troubleshooting….I determined the burning of oil is coming from the rear cylinder by removing muffler and watching the exhaust at each pipe…see little puffs coming from rear exhaust outlet only…
I know when I reassembled, I could not remember which way the arrows are supposed to point with the pistons…they looked identical either way, so I just put it together so both piston’s arrow faces forward. Is this my issue? I think each are supposed to point towards exhaust???? only other thing I can think of is maybe bad valve seals (I have them leftover from gasket kit but didn’t install them)…There is not any oil blow by in the air filter box, no external leaks, compression test shows 165lb on front cylinder and 175lb on rear cylinder. both spark plugs look nice and tan but tail pipe is showing evidence that exhaust is burning oil. My other 07 machine has over 7800 miles and does not use oil so I did not replace the rings when I went through this motor. Do you guys think I should just try replacing the valve guides 1st and see how it goes??? or do I bite the bullet and pull the heads off again, install new rings, maybe change direction of piston on rear cylinder????……maybe time for a mrrpm big bore kit?? =) sorry for the long post