Hello Jose,
(BTW, it's Leif who is planning to work on this kris
)
I'm with you and also strongly recommend heating the base of the blade with an open flame: either a candle and lots of patience or a very gentle/flickering torch flame and being even more careful! Once the heat dissipates into the tang, it is usually fairly easy to remove the blade. Don't worry, the flame doesn't hurt the blade but try to get as little direct heat at the hilt. I usually wrap the grip with some cloth and wear gloves. Especially for the pommel this is a way more gentle approach than the cooking procedure described above! (Not needed for any SEA blade I tried to remove and I also doubt it is really called for when working things khukuri - heating Nepali blades did for me so far but my experience is admittedly very limited.)
The clamp is quite loose (looks a bit large for this kris) - once the resin softens due to the heat, it should be easy to gently bend it aside so that the blade can be removed from the hilt. When the tang starts to wiggle when gently pulling and twisting blade vs hilt, keep gently heating the blade until the tang comes off easily. If it doesn't, let it cool down and try again next day; even stubborn ones do come off after a few cycles.
Regards,
Kai