On Wed, 12 Oct 2011 10:05:18 -0700 (PDT), "William R. Walsh"
wrote:

(snip)

What I really want to know, though, is whether or not a drop-in
replacement with more current delivering capability than the LM340 or
78xx series exists. I've looked halfheartedly over the years but never
found anything. I could always build a more capable regulator board
and hack it in there, but I don't really feel like doing that. A fan
would be easier and faster.

Alternative 3-terminal linear regs will still dissipate the same
amount of heat regardless of their current capability.

If the problem is in the load (i.e. faulty components) then that
should be where you focus your attention.

If the real problem is the load current and the consequent thermal
issues (i.e marginal/poor design vs SOA) then measure the actual load
current and consider a drop-in switcher such as the (TI) PT78T112V or
(RECOM) R-7812.