The 32-20 I consider it an antiquated cartridge. But if the 32-20 is indeed legal to take a deer in your hunt area with? Your well within your Rights to use that (1889) Marlin of yours. I would advise: Place your first shot well and consider the necessity of a follow up shot without hesitation and perhaps more than two even may be required to harvest your deer with. Good Luck with your aspiration Sir.
S/S Mc G.
"Do not follow where the path leads, rather go where there is no path and leave a trail."