There is from the manufacturer Philips of my LED in H4 socket a compatibility list.
There are monthly new models and brands included in the list, see the bottom of the page. I have not found a Morgan yet...or maybe overlooked.

https://www.philips.de/c-e/au/autolampen/scheinwerfer/led-compatibility-list.html

Another manufacturer, Osram, allows my 4/4 to run LED h4 in Germany. Just have a look. That was not the case when I bought the Philips lamp.

https://www.osram.de/am/night-breaker-led/index.jsp#_m603__accordion_1

I will now do the devil and buy Osram and throw away Philips....
Rather I wait for the extension of the Philips list.

It is an opaque German jungle of overbearing bureaucracy and case-by-case decisions. There are approvals for all sorts of cars of different years....

'14 4/4 graphite grey