Do you want something like this? Please check and comment if this is not what is expected.
Also please rectify any syntax errors.
SELECT T1.[Account No], T1.[IV Total], T2.[GL Total] FROM
(
select A.ACTNUMST as [Account No], sum(B.EXTDCOST) as [IV Total]
from GL00105 A
INNER JOIN SEE30303 B on A.ACTINDX = B.IVIVINDX
group by A.ACTNUMST
) T1
INNER JOIN
(
select A.ACTNUMST as [Account No], SUM(C.PERDBLNC) as [GL Total]
from GL00105 A
LEFT JOIN GL10110 C on A.ACTINDX = C.ACTINDX
group by A.ACTNUMST
) T2
ON T1.[Account No] = T2.[Account No]
Hope this helps