Any IM or subq is 100% absorbed. The only variable is rate of absorption. Injecting into gluts is a bad idea as there are major blood vessels and nerves and careful mapping [site selection] is required. Asking someone to do this is bad. You cannot really see what you are doing and viewing with a mirror presents its own problems.
I suggest subq twice a week to provide steadier T levels allow for proper E2 management with anastrozole at times of T injections. Anastrozole is competitive with T and needs to match serum T levels.
Smoother T delivery helps mange T–>E2 by avoiding peaks in that conversion. Avoiding T peaks also can be helpful for guys who have TRT induced blood thickening. Smoother T levels may also be better for mood support for some guys.
Injected T is testosterone+ester_group that allows the T+ester to dissolve in oil. Injected oil slowly absorbs and then ester groups are removed yielding [bio-identical T] which is a time release T delivery.