Cut out unwanted pieces of a lastname with vbscript

lastname = "DE' CA-R LO III"

'separate lastname by spaces into an array
a = split(lastname," ")
new_lastname = a(0)

for i = 0 to ubound(a) -1 ' add each chunk of the last name to the final string
'the last piece of the last name is not added if it is less than 4 characters (such as III, II, I, etc)
    if i + 1 = ubound(a) and len(a(i+1)) > 3 then
        new_lastname = new_lastname + a(i+1)
    elseif i + 1< ubound(a) then
        new_lastname = new_lastname + a(i+1)
    end if
next

new_lastname = Replace(new_lastname,"-","") 'take out hyphens
new_lastname = Replace(new_lastname,"'","") 'take out punctuations

wscript.echo new_lastname