Weapons in Pioneer Battalions and Royal Engineer Companies in March 1918

[Sappersnooper]

I am currently studying Fifth Army in March 1918 and I have noted that the reduction in infantry battalions forced many divisions to adopt the pioneer battalion and the 3 RE field companies as their only reserve. What were the relative (full establishment) strengths of pioneers, RE field companies  and standard infantry battalions in March 1918? What was the difference in fire support weapons such as Lewis Guns, Stoke mortars and rifle grenades? Thanks in advance for any responses.