Hi Garry;
The only Dragoons that served in Burma were the:
3rd Carabiniers
25th Dragoons, who were formed at Stalkot, India on 1 Feb 41.
The Welsh Battalions that served in Burma were Infantry:
The Royal Welch Fusiliers - 1st and 2nd Battalions
The South Wales Borderers - 6th Battalion
The Welch Regiment - 2nd Battalion
Thats about it Garry.
Cheers
Garry, I think your friend was refering to the 3rd Carabiniers (Prince of Wales's Dragoon Guards)