My Quadra 75 engines were ran for years with a 32:1 mix but for the last two seasons I have ran them at 50:1. Use a good 2 stroke oil such as Pennzoil air cooled. There are dozens of threads here on RCU about oil so I won't go into that here. Do a search and you will find hours (maybe days) of reading on the subject. 32:1 is 4 oz. of oil per gallon, 50:1 is 2.56 oz. per gallon. Anything at or between those amounts should be fine for your engine.

As for needle settings, again do a search here on RCU for tuning proceedures .... many to choose from. Sorry, not enough time here at work to write a complete description at this time. Your engine will start and run with both needles set between 1 1/2 to 2 turns open .... adjust from there as needed. Does your engine have a spring starter? If so, that will make starting much easier but these can be started OK with a brisk flip of the prop through a wide arc to get a good spark from the mag. How long has it been since your engine was last run? It may be due for a carb kit or at minimum an inspection of the pump diaphram and filter screen.

Is this your first gasser? If so, you have a good one but respect it and be careful around that big prop.