Sounds like it's going well and you did your research. I think you are on the money with your gh peptides. The only thing I'd correct though is your assumption that igf1-lr3 will not go systemic if injected in the muscle vs sub-q. The half-life is what we're looking at here. bio-identical (original) igf-1 is very fast acting, like regular mgf, that is why people claim it has a site-specific effect. It is innactive so quickly that it has little chance to do anything outside the muscle in which it was injected. But, igf1-lr3 is modified in such a way that causes it to be resistant to break down and to being bound by igf-1 binding proteins. Therefore it tends to circulate in your system for hours, no matter where you inject it. You'll notice a bit of swelling in the muscle from im injections with it vs sub-q. But, that's not because it went to work and caused localized muscle growth, it's just temporary irritation. You're basically getting the nutrient disposal benefits from it- as you stated you were looking for from it. And, for that, it works very well. You can eat like a horse on it right after injection and not put on any fat to speak of.
A little trick to the gh peptides- Using gh itself 15 minutes post injection causes a severe "spike" in the pulse created by your ghrp/grf combo. I can't remember for sure just how much, but it really increases the output of gh by your body and your system sees it still as a "natural" pulse vs an exogenous injection. This is a weird statement, I know. But, it has to do with the timing. Also, there was a study done in the late 90s that showed using melatonin (10 mg) 1 hr before using ghrh (what we call grf) doubled the output of gh release normally caused by the grf! So, when I do my nightly dose I take 9 mg of melatonin (3 x 3 mg pills) 1 hr before my ipamorelin and mod grf. Then, 15 min later I take just 1 iu of GH. The results are surprising using it all this way. You get an incredible "bang for your buck." If you need a reference to the study, let me know, I'm sure I could track it down again.
Sounds like it's all going well and you know your stuff! Keep up the good work and getting great results!