The tank will come off of any Savage, w/o removing the petc0ck. The rubber bushings are just snug and make it hard. One trick to remove the tank easily requires removing the tank once, and upon reassembly just put a little bit of Vaseline on the rubber bushings. From then on it will be much easier. And, yes it is tight and will scratch the frame, but you just have to push the tank up and slightly to the left to get it off.
As for the plug...it is a PITA to reach, but why do you need to have such easy access? I'm running a 3 year old plug in mine and have never had to remove it for anything other than an inspection...I mean, I've never had any troubles that related to the plug. It is pretty low maintenance.
The Suzuki engineers were a little short sighted on the chrome covers though. The left cover has that upside-down bolt that requires the cover to be raised up to remove. Just another little quirk about the Savage. However, if you ever remove the head cover, then you can actually turn the bolt upside down with the nut on the bottom....I wonder if the cover could be slotted to remove the cover from the side off the bolt. Hmmmm.