The Lords are an integral part of Parliament. Vote for supremacy of Parliament over Brussels and that's what you get: all of Parliament not just the bits you like.

By and large, reform of the House of Lords is something "the left" argue for, and "the right" argue against. I am fairly confident most Rees Mogg pronouncements on the Lords will be in support of it as is, unless his recent idea to neuter it by making 200 new Lords to force his personal view of Brexit through.