Halfrauds does free battery tests
You can measure drain with your fluke, just don't start car with it connected, sure a clamp-on is easier but in lack of better fluke will do
There's loads of give in heater duct, be a little brutal to get a large spacer in for room to work, found it easy bit fiddly.
Tip - for the things you can't see, take a picture from any angle and blow it up- a small camera or a phone
like lucas a lot, use any good oil, 10w40 as prescribed, or mobil 10w 50 very good, bit pricey - i use shell helix 10w40 change 1/2yearly doing very little miles, engine love frequent change