Heating them will be difficult. The aluminum head will suck the heat out just as fast as you can pour it in.
And if you believe in Prayer say one BEFORE you start. I hate helicoils but i removed one and installed two for my Son the other day. Like its said above a small pick or screwdriver and a pair of needle nose pliers. I have a set of left handed drill bits that I was thinking about trying but it didn't come to that. We used mostly keenserts in the steel mill for thread repairs.
When I did my Thread Insert Deathmatch I found no benefit to using the Keensert style key locking insert. In instrumented testing that style (Recoil brand) did not perform as well as the Helicoil.
In torque testing it scored the same as Helicoil and better than the TimeSert.
When it came to the pull out resistance it began to yield about 10% lower than the Helicoil and ripped out of the test bar at 900 lbs less force (again, about 10%) too. In fact, it scored the same in this area as fresh threads in 6061 aluminum.
Here's a link to the testing video starting at the summary:
https://youtu.be/LpDduCVUy6w?t=28m39s
