I had an electrician install a generator interlock kit in my Square D Homeline panel. It turns out my 200 amp panel and sub panel were both full so tandem or piggyback breakers were used to free up space for the 30 amp double pole generator breaker. My tag on my panel states that the panel is a 30 circuit 40 circuit max so the electrician said that tandems could be used. The problem was that the tandem breakers did not fit into the spaces he made available by moving other breakers around so what he did was "chip" away the plastic on the back slot of the breaker to make the slot longer so it would seat down onto the bus bar. After doing a little reasearch I discovered that there are spaces near the bottom of the panel that are made for tandem breakers. My question is this...should I have this electrician return and do this the right way or is what he did OK? I know technically what he did was wrong but is there any danger issues to what he did? I do not have any more plans to add future circuits so I will not overload the panel by adding more circuits that the panel is rated for.

I'm replacing two electric ovens with new Miele ovens in existing undercounter locations. My question is the manufacturer 4 wire wip have crimp ends on all wires. The instructions however say they should be connected at junction box. Do I simply cut the crimp ends away and attach at JB with wire nuts? Also, my existing JB were located under the cabinet base that the ovens sit on. Ovens are side by side horizontal under counter and sitting just on top of kickplate on 3/4 inch plywood. Plywood is cut away to expose subfoor below where J Boxes are also located. There was no cover on either box and the boxes were just sitting on subfloor. Question: does this meet code? Should I secure and cover JB after connections made? Can JB be attached to exposed basement ceiling below so that access is easier then pulling out oven to get to box? Thanks